This invention relates to an accumulating conveyor, and more particularly to an accumulating conveyor for transverse transportation of elongated stock, such as pipes, tubes, rods, bars and like articles.
Various types of accumulating conveyors are available. For example walking beam accumulating conveyors, such as the type illustrated in U.S. Pat. No. 5,454,466, and accumulating conveyors which utilize a continuous moving conveyor portion which accumulates articles and delays or halts progress of the articles by lifting the articles from the continuous conveyor are known. Other accumulating conveyors accumulate articles on a stationary conveyor which is selectively operated to advance the articles, and yet others use stationary portions to accumulate articles, the articles being engaged for advancement by selectively operated article engaging mechanisms.
There are also known conveyors for conveying elongated stock in a transverse direction which include a number of elongated substantially parallel racks which extend in the direction of desired conveyance. Each rack is provided with two or more adjacent rows of teeth extending longitudinally with the rack, and the teeth of one row are staggered with respect to the teeth of the other row and a drive is connected for alternately raising one row of teeth above the other whereby elongated stock placed transversely on one end of the conveyor racks will be moved to the other end of the conveyor racks for offloading. Examples of this category of conveyor are illustrated in U.S. Pat. Nos. 701,024; 793,296; 863,842; 2,796,780 and 3,891,081, and Japanese Patent No. 58-162416. The latter referenced conveyor described in the Japanese reference operates in a different manner than the previously mentioned conveyors, but nevertheless, is in the same category as described.
An adequate accumulating conveyor incorporating this particular category of conveyor for elongated stock is not available on the market and it is accordingly an object of the present invention to provide such an accumulating conveyor which is inexpensive to manufacture, economic to operate and most importantly extremely effective in not only conveying the elongated product in a transverse direction, but to further effectively and efficiently accumulate the elongated stock between ends of the accumulating conveyor.
The accumulator conveying apparatus of the present invention is provided for elongated stock, such as tubes, rods, bars and the like, and is comprised of at least three independently operable conveyor banks arranged for sequentially transferring elongated stock from one bank to the next. Each conveyor bank or section consists of a conveyor type of the prior art category previously described wherein each conveyor bank or section includes a plurality of elongated substantially parallel racks which extend in the direction of desired conveyance and each rack has at least two adjacent rows of teeth extending longitudinally along the rack. The teeth of one row are staggered with respect to the teeth of the other row and a drive is connected for alternately raising one row of teeth above the other whereby elongated stock placed transversely on one end of the racks will be moved to the other end of the racks of each conveyor bank or section for offloading or for transfer to an adjacent conveyor bank.
Sensors are provided on each conveyor bank and positioned for sensing the presence of elongated stock on each conveyor bank and for energizing and de-energizing selected ones of the conveyor bank drives whereby elongated stock transversely fed onto one end of the entire accumulator conveying apparatus is moved to the other end of the accumulating conveying apparatus and in addition the elongated stock is accumulated thereon between the conveyor ends.
The teeth provided on the conveyor may be of resilient material for preventing marring of elongated stock being conveyed thereon. The parallel conveyor racks may be comprised of bars with two or more rows of teeth projecting from the bars, and the drives are connected for synchronously oscillating the conveyor bars on their longitudinal axis of rotation. This is the type of conveyor and type of conveyor drive are described in the aforementioned U.S. patents. However, the accumulating conveyor of the present invention may also incorporate conveyor banks or sections therein which operate in the manner described in the afore-referenced Japanese patent.
If desired, adjustment may be provided for adjusting the actual degree of staggering between the adjacent rows of conveyor teeth on each conveyor rack.
Normally the sensors are positioned whereby intermediate conveyor banks are controlled for accumulating elongated stock being conveyed thereon and the last conveyor bank drive is further connected to a demand sensor for delivering a single piece of elongated stock upon demand from the last conveyor bank to a subsequent material handling system. In this manner, elongated stock is fed one at a time to a subsequent material handling system for operations to be performed on the stock, and backup elongated stock is accumulated on the conveyor system on the intermediate conveyor banks or sections.